The progress and problems of the 'Endemic Section' of St Helena Island
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ORYX VOL 31 NO 3 JULY 1997
The progress and problems of the
'Endemic Section' of St Helena Island
Doug Smith
St Helena is a small Atlantic island with an unusual and remarkable flora and
fauna but with a legacy of ecological destruction typical of oceanic islands. The
efforts of the island's governmental Endemic Section in the conservation of the
flora and fauna is examined alongside the objectives of the section as listed in its
current business plan. The worthy level of progress that is evident (including the
rediscovery of species, habitat restoration and a high level of environmental
awareness) is attributed to local ownership, an emphasis on education, and
pragmatism and flexibility. The problems that limit the section's long-term
effectiveness are funding, limited baseline ecological information and limited
technical understanding.
Background plant species and 10 of the plant genera are
endemic to the island (eight of the genera are
St Helena is a small isolated island (122 sq km) monospecific, indicating their evolutionary
in the South Atlantic Ocean (15°56'S, 5°42'W), isolation). There are 14 endemic fern species
which arose from volcanic activity to the east including the St Helena tree fern Dicksonia ar-
of the mid-Atlantic rift over 14 million years borescens. Almost nothing is known of the
ago. The island has a complex topography of island's lower plants.
ridges and deep gorges, plains and hills, the Of St Helena's approximately 1100 terres-
main feature of which is the high central ridge trial invertebrate species, 400 are endemic to
surrounded by radiating valleys. The island's the island: they include 77 endemic species of
coast consists largely of precipitous cliffs, in- weevil (17 endemic weevil genera and four
terrupted by small bays. St Helena is often de- endemic weevil tribes) and 49 endemic species
scribed as 'an emerald set in stone', alluding of spider (Basilewsky, 1970, P. Hammond
to its verdant centre of pasture, smallholdings, pers. comm.). Subfossil evidence indicates the
plantation forestry, and indigenous veg- presence of a total of five endemic land birds
etation, surrounded by rocky wastelands and on St Helena in recent history, including a
eroded 'badlands' (see Figure 1). large species of hoopoe Upupa antaios and a
The geographical position of St Helena and cuckoo Nannococcyx psix. One species of land
the timing of its emergence have given rise to bird remains: the wirebird Chamdrius sanctae-
an endemic flora and fauna of exceptional helenae, which is a relative of Kittlitz's sand
taxonomic isolation and scientific interest, plover C. pecuarius of southern Africa. Two en-
analogous in its level of endemism to that of demic petrels probably also remained on the
New Caledonia (Mittermeier et al., 1996). island at the time of its discovery (Olsen,
Recently Wilson (1992) described St Helena's 1975). Now, indigenous seabirds are restricted
biosphere as only 'one step removed from a to offshore islets owing to predation by cats
satellite colony in space'. and rats. The island's poorly studied marine
Over a century ago, St Helena's plants were life further affirms St Helena's status as an
described by Hooker as 'fragments from the 'evolutionary laboratory' (Edwards, 1990).
wreck of an ancient world' (Melliss, 1875). Unfortunately, St Helena is typical of
Almost all St Helena's indigenous flowering oceanic islands that suffered high levels of
218 © 1997 FFI, Oryx, 31 (3), 218-224
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destruction and degradation after their dis- (known as the Endemic Section) was based in
covery by European naval powers. The de- a small nursery facility established in 1984
cline of St Helena's biodiversity began with financial help from the World Wide Fund
following the island's discovery in 1502, when for Nature (WWF). With the help of the
goats and pigs were established there for re- International Institute of Biological Control,
victualling purposes. Destruction intensified facilities were also established to rear and re-
after settlement began in 1659 (Cronk, 1993). lease biological control agents Hyperaspis pan-
Past habitat destruction and fragmentation of thera (Coleoptera: Coccinellidae) for a
the remaining indigenous habitat has left a homopteran Orthezia insignis (Homoptera:
legacy which, in combination with relentless Ortheziidae) which threatened the last small
introductions of exotic plants and invertebrate patches of indigenous gumwood woodland
pests, continues to push the island's remark- (Commidendrum robustum) that historically
able biodiversity into oblivion. covered over 60 per cent of the island. The re-
Currently, 13 of the island's endemic lease programme was successful and the fu-
flowering plants have been categorized in the ture of the woodland is now secure.
IUCN Critically Endangered category: this in- Benjamin also ensured that much of the sec-
cludes those that have been reduced to a tiny tion's time was spent educating the public and
handful of individuals and those that, with schoolchildren about St Helena's flora. There
100-150 individuals remaining, are relatively are now virtually no islanders who do not un-
common (Maunder, 1995). The decline in in- derstand the meaning of the term 'endemic' or
vertebrate species is unknown because the who cannot recognize a St Helena ebony, and
most recent thorough survey was carried out public interest is reflected in membership of
in the 1960s. It is feared that many of the the recently formed St Helena Nature
island's invertebrates will have followed in Conservation Group. The section pioneered
the footsteps of the giant earwig Labidura her- habitat restoration and species rescue on St
culeana which reaches up to 78 mm in length: Helena, and is arguably at the forefront of
40 specimens of this earwig, the world's global efforts in restoration ecology.
largest, were collected in 1967 but recent ef- In 1993, prompted by the 1992 United
forts to rediscover any individuals of this Nations Conference on Environment and
species have failed (Clarke and Veal, 1989). Development and by lobbying from the UK
Dependent Territories Forum, St Helena's
Agriculture and Forestry Department, in col-
Conservation on St Helena in the laboration with the International Institute for
twentieth century Environment and Development (IIED) and
Royal Botanic Gardens, Kew (RBG), initiated a
George Benjamin is a St Helenian who devel- Sustainable Environment and Development
oped an expert knowledge of St Helena's flora Strategy (SEDS; for a full discussion of SEDS
during his work as a forest guard for the see Maunder et al., 1995). As part of SEDS,
island's Agriculture and Forestry Department measures to conserve the endemic flora were
in the 1970s and 1980s. He, with others, redis- intensified. A consultant from RBG visited the
covered several St Helenian endemic plants island in February 1995 to make recommen-
that were previously assumed to be extinct: dations for species rescue programmes and
the she cabbage tree Lachanodes arborea in 1976; habitat conservation. Benjamin retired in 1995,
the St Helena olive Nesiota elliptica in 1977; and but the section now has a larger number of
the St Helena ebony Trochetiopsis ebenus in staff than ever and key members of staff are
1980. In 1984, Benjamin established a small receiving overseas training. Contemporary to
section of staff at the Agriculture and Forestry the development of the SEDS was the first in-
Department to work on the propagation of the tensive academic research to be focused on
endemic plant species. any of St Helena's species: doctorate research
This Environmental Conservation Section in Trochetiopsis, an endemic genus of two
11997 FFI, Oryx, 31 (3), 218-224 219
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Figure 1. A view south-west
from St Helena's central ridge. It
indicates St Helena's remarkable
topography and the dramatic
contrast between the vegetated
uplands and the encircling
eroded wastelands (D. Smith).
species, one of which has passed through a park is refuge to almost all of the remaining
bottleneck of two individuals while the other fragments of St Helena's endemic tree-fern
has endured a bottleneck of one (Rowe, 1995). thicket, which are threatened by invasive New
The Agriculture and Forestry Department Zealand flax Phormium tenax (Smith and
hosted a conference in February 1995, to allow Williams, 1996; Smith, in press; see Figure 2).
discussion of the SEDS among representatives
of governmental organizations, the private
sector and the public. Among the discussions Progress
Q. C. B. Cronk (who worked with Benjamin
over many years) made two proposals: the Progress in terms of sustainably increased sur-
creation of St Helena's first national park; and vival prospects for the endemic species is
the establishment of a biological research summarized in Table 1. The table shows
station. The first proposal was taken forward achievements against the four objectives of the
and excited much public debate, culminating Endemic Section as defined in the section's
in the gazettement of Diana's Peak National business plan drawn up in 1995. The small
Park in March 1996. A management plan for scale of the island and of its conservation
the national park was completed at about the problems may have aided the substantial
same time and is being implemented. The progress that is evident. However, there are
Figure 2. Fragments of tree-
fern thicket (A) are shown
surrounded by exotic New
Zealand flax plantation (B)
on this hillside in Diana's
Peak National Park. Note
also the areas cleared of flax
plantation (C) in
preparation for trials to
investigate tree-fern thicket
recreation (D. Smith).
220 • 1997 FFI, Oryx, 31 (3), 218-224
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key features of the work of the Endemic
Section that I suggest have ensured success, ir-
respective of the island's small scale: local
ownership; a focus on education; and pragma-
tism and flexibility.
Local ownership
As described above, conservation on St
Helena was pioneered by George Benjamin: so
from the very start the efforts were locally
'owned'; and the staff of the endemic section
wanted to build gradually on the work, Figure 3. One of a set of stamps released in August
1995 depicting St Helena's unusual invertebrates.
simply because it was their work and rep-
This example, the golden sail spider Argyrodes
resented their personal endeavours. mellissii, is one of 48 species of spider endemic to the
Furthermore, as the work gained more promi- island.
nence, the public became proud of and sym-
pathetic with work to conserve the endemic
species because it was carried out by commit- Pragmatism and flexibility
ted islanders and because the endemic plants The work of the section was based upon
represented something uniquely St Helenian. simple rules rather than complex theories of
This experience underscores the importance conservation biology. Despite the lack of
of ensuring local involvement to achieve long- scientific research into any of the endemic
term conservation success and is comparable plants, the section did not hesitate to follow
to experience elsewhere (for example Child, basic rules to stop and reverse species decline.
1995). Despite St Helena's small scale, it has a A good example (which also illustrates the
long history of development projects with no commitment to education) is the establish-
local ownership, which have ultimately failed. ment of endemic trees within the grounds of a
In contrast to conservation projects elsewhere, school in order to provide an informal and ac-
however, the work of the Endemic Section cessible seed orchard.
was unusual in having a reliable source of
funds from the St Helena Government and the
island has no direct land-use conflicts. Problems
Despite the progress that has been made, cer-
Focus on education
tain factors affect the potential for the current
The emphasis that was placed on education, success to result in sustainably reversed con-
either through regular radio interviews or servation threats (see Table 1). These include
through work with primary school children, restricted funding, lack of basic ecological in-
has further reinforced the interest that formation and technical problems.
islanders have in their biological heritage and
their wish to ensure success. The work of the
Funding
UK Dependent Territories Forum and the St
Helena Nature Conservation Group has also The most outstanding constraint upon con-
raised awareness through the sale of posters tinued conservation success on the island will
and the issue of 'endemic' postage stamps be restricted funding, especially amid the cur-
(Figure 3). rent climate of public sector reform and econ-
omic recession on the island. St Helena, as a
dependent territory of the UK, is not eligible
for funding from the Global Environmental
) 1997 FFI, Oryx, 31 (3), 218-224 221
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Table 1. The progress, current priorities and problems of the Endemic Section of St Helena summarized
against each of the four respective objectives of the section in the business plan for 1996/7
Progress so far Priorities now Problems
Objective 1. To save and rehabilitate St Helena's endemic habitats and increase their extent
1.1 Since 1984 relict flax plantation was cleared 1.1 Clearance of invasive 1.1 No scientific basis of
and stands of endemic trees were established plants from tree fern ecological understanding
at High Peak. thicket at High Peak. of endemic habitats.
1.2 Patches of gumwood woodland rescued 1.2 Integrated control of 1.2 Very steep terrain limits
from an introduced pest by successful introduced pests of physical work in many areas.
biocontrol, beginning in 1993. endemic species. 1.3 No technology for cheaper
1.3 Clearance of exotic scrub separating the 1.3 Establishment of and more successful control of
two remaining patches of endemic gumwood endemic gumwood invasive plants and pests.
woodland (which covered 60% of the island seedlings to link the 1.4 Limited seedling supply for
in 1502). fragments. supplementation planting.
1.4 Implementation of a rescue plan for the 1.4 Continuation of the
tree fern thicket of Diana's Peak began in 1995 rescue plan to remove
(8.4 ha of tree fern thicket cleared of invasive invasive flax from all tree
flax; 2-ha restoration trial set up). fern thicket and to
1.5 Diana's Peak National Park declared in begin tree fern thicket
March 1996, to complement the 5-year recreation of key locations.
rescue plan. 1.5 Pursuit of further
1.6 Flax cleared around isolated tree ferns funding to support rescue
in 'the Depot' in 1996. plan and interpretation
1.7 Leader of habitat management team for the park.
undergoing training in South Africa.
Objective 2. To recreate endemic habitats in selected areas as they originally grew
2.1 Successful control of feral goats since 2.1 Continued surveillance 2.1 Habitat rescue in the wetter
1960s has allowed recolonization of endemic for feral livestock. parts of the island is higher
halophytes in dry rocky coastal zone of 2.2 Further and more priority than habitat
St Helena. species-diverse plantings recreation in drier parts:
2.2 Successful establishment of gumwood at Horse Point Plain. funding is limiting.
trees at Horse Point Plain, an eroded part 2.3 Control of rabbits and 2.2 Limited seedling supply.
of the island. prevention of new exotic
2.3 Establishment of stands of St Helena colonization in the south-
ebony in a further eroded area. west of the island where
natural colonization of
endemic plants is most
successful.
Objective 3. To rescue endemic species from the brink of extinction (ensuring all genetic variation is retained)
3.1 Rediscovery of several plant species 3.1 Intensive rescue and 3.1 Technical problems of
thought to be extinct. breeding programmes for pollination and propagation:
3.2 Nursery establishment. each of the critically for example the St Helena
3.3 Successful propagation of most endangered plant species olive has a self-incompatibility
rediscovered species. to ensure propagation and mechanism and is reduced to
3.4 Programme of propagule collection and seedling production is four individuals.
seed orchard (ex situ genebank) development based on genetic security. 3.2 Hybridization problems in
under way. certain genera, uncertain
3.5 Doctorate research on endemic redwood. knowledge of taxonomy of
3.6 Further nursery improvements including certain genera.
purchase of equipment for seed storage.
continued...
222 11997 FFI, Oryx, 31 (3), 218-224
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Table 1. (Continued) The progress, current priorities and problems of the Endemic Section of St Helena
summarized against each of the four respective objectives of the section in the business plan for 1996/7
Progress so far Priorities now Problems
3.7 Monitoring survey established for the 3.3 Breeding programmes to
species of dryland areas usually assumed to be ensure genetic security have to
abundant. be based upon assumptions
3.8 Monitoring of the endemic wirebird and regarding phenotypic fitness,
some monitoring of invertebrates carried out take years to implement, and
at intervals. require sustainable funding.
3.9 Nursery manager on training at Royal
Botanic Gardens, Kew.
Objective 4. To raise public awareness and appreciation of St Helena's endemic heritage
4.1 Regular radio talks by section staff 4.1 Formalized education 4.1 Time and funding for
continuing for some years. in schools across the educational activities are
4.2 Sales of endemic seedlings as garden curriculum through constrained by the Section's
plants to public very popular. information packs for other priorities.
4.3 Tree planting and education in schools. teachers.
4.4 Establishment of the George Benjamin 4.2 Continued work in
Arboretum of endemic trees for public local newspaper and radio.
education. 4.3 Further improvements in
4.5 Regular conservation bulletin established access to Diana's Peak and
in local newspaper from 1995. High Peak.
4.6 Improved access and interpretation for
Diana's Peak National Park and High Peak.
4.7 Colour National Park leaflet/poster for
public sale.
Facility, a problem experienced by other de- tourism industry (St Helena Government,
pendent territories of former colonial powers 1996). This was the reasoning for Cronk's pro-
(Mittermeier et ah, 1996). posal for a biological research station. In fact
carrying out research on St Helena is very
straightforward because of the co-operative
Lack of basic ecological information
government and a friendly public.
Technical solutions that enable more effective
solutions from each conservation pound or
Technical problems
dollar are limited while scientific studies of
the island's terrestrial and marine fauna and Technical problems continue to hinder
flora are few and far between. Furthermore, St progress with the rescue of particular species.
Helena's biological interest has received vir- The lack of understanding of flower structure
tually no publicity owing to the lack of botan- and pollination mechanisms will pose particu-
ical and zoological research. Thus the world at lar problems for plant propagation. For
large (including donor agencies) remains un- example cross-pollinations cannot yet be
aware of, and therefore indifferent to, St Helena's carried out on the endemic whitewood
conservation value, and applications for fund- Petrobium arboreum because of its unusual
ing are less likely to meet with success. composite flowers. The St Helena olive Nesiota
The absence of global publicity also under- elliptica is reduced to four individuals (one
mines the ability of the island to 'add value' to vegetatively propagated from the last wild in-
its flora and fauna through ecotourism as part dividual and three offspring of self-polli-
of the developing 'high value - low volume' nations from that individual) but can produce
11997 FFI, Oryx, 31 (3), 218-224 223
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no more than very occasional seeds due to a Clark, D. and Veal, R. 1989. The Project Hercules
self-incompatibility mechanism. Furthermore, Expedition to St Helena. Unpublished report,
there is a hybrid species Trochetiopsis x ben- Zoological Society of London.
Cronk, Q.C.B. 1993. Extinction and conservation in
jaminii between T. ebenus and T. erythroxylon,
the St Helena flora: the palaeobiological and eco-
and a possibility of hybridization problems in logical Background. Boletim do Museu Municipal do
three further genera. Such hybridization was Funchal, Suppl. 2, 69-76.
avoided in historical times due to allopatry or Child, G. 1995. Managing wildlife successfully in
to the absence of subsequently introduced Zimbabwe. Oryx, 29,171-177.
generalized pollinators. Edwards, A. 1990. Fish and Fisheries of St Helena
Island. NB Print & Design, Washington, Tyne &
In the rescue of habitats, invasive exotic
Wear.
plants and pests present technical problems: Maunder, M. 1995. Endemic Plants — Options for an
New Zealand flax Phormium tenax invades Integrated Conservation Strategy. Unpublished
tree-fern thicket through the copious pro- Consultancy Report, July 1995, Royal Botanic
duction of seeds and it is impossible to com- Gardens Kew, for the Government of St Helena
pletely physically remove the flax on the very and the Overseas Development Administration.
steep ground to which the indigenous tree Maunder, M., Upson, T., Spooner, B. and Kendle, T.
fern thicket is now limited; exotic moth larvae 1995. St Helena: Sustainable Development and
Conservation of a Highly Degraded Ecosystem. In
(Opogona spp.) threaten adult trees of some
Islands: Biological Diversity and Ecosystem Function
species such as the he cabbage tree (eds. P. M. Vitovsek, L.L. Loope and H.
Pladaroxylon leucadendron. Adsersen), pp. 205-217. Ecological Studies 115,
Springer Verlag.
Melliss, J.C. 1875. St Helena. Reeve, London.
Conclusion Mittermeier, R.A., Werner, T.B. and Lees, A. 1996.
New Caledonia - a conservation imperative for an
ancient land. Oryx, 30,104-112.
The remarkable flora and fauna of St Helena is Olsen, S.L. 1975. Palaeornithology of St Helena
now in a critical period of its long history: it Island, South Atlantic Ocean. Smithsonian
has been devastated since human discovery of Contributions to Palaeobiology, 23,1-49.
the island in 1502, but great progress has re- Rowe, R.E. 1995 The population biology of
cently been made in conservation and resto- Trochetiopsis: a genus endemic to St Helena. PhD the-
ration efforts. With sustained attention, sis, Oxford University.
Smith, D.J. 1996. A rescue plan for the threatened
funding and an improved technical know-
tree fern thicket of Diana's Peak National Park, St
how, such progress can be maintained and Helena. Botanic Gardens Conservation News, 2 (7),
built upon; without these things the island's 46-18.
species and habitats will enter a brief final Smith, D. And Williams, N. 1996. Diana's Peak
phase - of extinction. National Park of St Helena: The Management
Plan for 1996-2001. Unpublished report, St Helena
Agriculture and Forestry Department.
Acknowledgements St Helena Government. 1996. Tourism Policy
Statement. Unpublished report, St Helena
Thanks to Nick Williams, Vanessa Thomas, Hazel Department of Economic Planning and
Bowers, Barry Thomas, Georgie Henry, Collie Development.
Richards, Mark Williams, Germaine Fowler, Wilson, E.O. 1992. The Diversity of Life. Penguin,
Leslie Benjamin, Eric Henry and the St Helena Harmondsworth.
Government.
Doug Smith*, Environmental Conservation Section,
Agriculture and Forestry Department, Island of St
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224 11997 FFI, Oryx, 31 (3), 218-224
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